Gau-21 trigger

ABSTRACT

A mechanism configured to be coupled to a gun to electronically fire the gun, such as a GAU-21 machine gun, from a location remote from the gun. The mechanism includes a lifter configured to be inserted into a rear portion of the gun proximate the gun&#39;s bolt latch bar. A lever is coupled to the lifter and is configured to lift the lifter and the bolt latch bar as the gun reciprocates during firing. An electronic actuator, such as a solenoid, is configured to drive the lever to responsively lift the lifter bar, wherein the mechanism is configured to reciprocate with the gun as it is firing.

PRIORITY CLAIM

This application claims priority under 35 U.S.C. 119(e) of U.S. Provisional Patent application Ser. No. 62/061,680 filed Oct. 8, 2014 entitled GAU-21 TRIGGER, the teachings of which are incorporated herein in their entirely.

TECHNICAL FIELD

This disclosure is directed to an electronic trigger mechanism for a gun, and more particularly for a GAU-21 gun.

BACKGROUND

A legacy mount for some weapons, such as a GAU-21 belt fed .50 caliber machine gun, only allows the weapon to be fired mechanically by a user. This may be because the gun reciprocates during firing. The GAU-21 gun is a machine gun typically used in aircraft or on vehicles.

SUMMARY

This disclosure provides a mechanism configured to be coupled to a gun to electronically fire the gun, such as a GAU-21 gun, from a location remote from the gun. The mechanism includes a lifter configured to be inserted into a rear portion of the gun proximate the gun's bolt latch bar. A lever is coupled to the lifter and is configured to lift the lifter and the bolt latch bar as the gun reciprocates during firing. An electronic actuator, such as a solenoid, is configured to drive the lever to responsively lift the lifter bar, wherein the mechanism is configured to reciprocate with the gun as it is firing.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates a perspective view of a conventional GAU-21 gun having an actuating mechanism including a solenoid mounted to the gun so that the mechanism reciprocates with the gun when fired;

FIG. 2 is an enlarged view of the solenoid and actuating mechanism mounted to the gun as shown in FIG. 1;

FIG. 3 is a top view of the actuating mechanism and the gun's back plate;

FIG. 4 is a left hand angled view of the actuating mechanism seen to comprise the solenoid mounted to a back plate trigger block;

FIG. 5 is a left hand angled view showing the gun's bolt latch bar in the resting position, where the gun is not firing. The bolt latch bar is not lifted by the lifter, so the gun bolt is held in the rearward position. The gun's back plate, the back plate trigger block, and the ball lock pin are all hidden for clarity;

FIG. 6 is a left hand angled view showing the gun firing, where the bolt latch bar is lifted by the lifter which allows the gun bolt to move freely;

FIG. 7 is equivalent to FIG. 6, but the gun's back plate, the back plate trigger block, and the ball lock pin are all hidden for clarity;

FIG. 8 illustrates an intermediate position, where the gun trigger is released and the gun will not fire;

FIG. 9 is equivalent to FIG. 8, but the gun's back plate, the back plate trigger block, and the ball lock pin are all hidden for clarity; and

FIG. 10 illustrates the rearward moving bolt (not shown), where the bolt hits the bolt latch pawl flap and knocks it off the limit of travel pawl.

DETAILED DESCRIPTION

Referring to FIG. 1, there is shown a perspective view of a conventional GAU-21 gun at 10. According to this disclosure, an actuating mechanism 20 is mounted to the gun 10 so that the mechanism 20 reciprocates with the gun 10 when fired. The mechanism 20 is mounted such that the gun's bolt latch bar is raised to fire the gun electronically.

Referring to FIG. 2, there is shown an enlarged perspective view of the actuating mechanism 20 mounted to the back of gun 10.

FIG. 3 is a top view of the mechanism 20 and a back plate 24 of gun 10. FIG. 4 is a left hand angled view of the mechanism 20 seen to comprise a solenoid 22 mounted to a body comprising a back plate trigger block 34. The back plate trigger block 34 is mounted to the gun's back plate 24 by inserting a front portion of the trigger block 34 into a square cutout of the back plate 24 and locking it in place using a ball lock pin 50 that extends through the trigger block 34 and the back plate 24.

FIG. 5 illustrates mechanism 20, where the gun's back plate, the back plate trigger block, and the ball lock pin are all hidden for clarity. The solenoid 22 is configured to pull a bell crank 26 using a clevis 28 which creates a mechanical advantage. The bell crank 26 is attached to a sliding bolt latch lifter 30 at the forward end of the mechanism 20. The lifter 30 has a vertically extending member comprising a plate 36 configured to slide in a vertical cutout channel 32 of the trigger block 34 (see FIG. 3 and FIG. 4). As the solenoid 22 actuates, the bell crank 26 rotates and causes the plate 36 of lifter 30 to move upward in the channel 32, as shown in FIG. 6 and FIG. 7. The vertical channel 32 ensures that the lifter 30 moves vertical as well, to vertically lift the gun's bolt latch bar 48. The plate 36 is configured to move parallel to the bolt latch bar 48 in the upward and downward direction.

A bolt latch pawl 40 is pinned to the lifter 30 and is spring loaded by a torsion spring 42 in the forward direction. As the lifter 30 moves upward, the bolt latch pawl 40 moves upward with it, pushing the limit of travel pawl 46 out of the way and lifting the gun's bolt latch bar 48, as shown in FIG. 7. When the solenoid 22 is released, the bolt latch pawl 40 is intermittently caught on the top surface of the limit of travel pawl 46 as shown in FIG. 8 and FIG. 9. The rearward traveling gun bolt hits the bottom flap of the bolt latch pawl and knocks it off the limit of travel pawl 46. The bolt latch pawl bottom flap stays pressed against the rear face of the bolt due to it being spring loaded.

FIG. 4 and FIG. 5 are both left hand angled views showing the bolt latch bar 48 in the resting position, where the gun is not firing. The bolt latch bar 48 is not lifted, so the gun bolt is held in the rearward position. The gun bolt face (not shown) is in contact with the bolt latch pawl flap 40. The bolt latch pawl flap 40 stays spring loaded forward by means of torsion spring 42 and the lower flap stays pressed against the gun bolt. The gun 10 is ready to be fired again in this position.

FIG. 6 and FIG. 7 are a left hand angled view showing the gun 10 firing. The bolt latch bar 48 is lifted by bolt latch pawl 40 by means of lifter 30 which allows the gun bolt to move freely.

FIG. 8 and FIG. 9 are a left hand angled view showing an intermediate position of mechanism 20, where the gun trigger is released and the gun 10 will not fire. The bolt latch pawl 40 gets caught on the limit of travel pawl 46.

FIG. 10 illustrates the rearward moving bolt (not shown), where the bolt hits the bolt latch pawl flap 40 and knocks it off the limit of travel pawl 46.

Spring 52 is the solenoid's return spring. Spring 52 forces the mechanism 20 to return back to its resting position, which is when the bolt latch lifter 30 is at its lowest position. The spring 52 must be strong enough to return the mechanism 20 to its resting position, which is not firing, but not so strong as to create too much resistance when the solenoid 22 is pulling against the spring force.

The foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present disclosure being limited solely by the appended claims. 

We claim:
 1. A mechanism configured to be coupled to a gun having a bolt and a bolt latch bar, comprising: a lifter configured to be inserted into a rear portion of the gun proximate the bolt latch bar; a lever coupled to the lifter and configured to lift the lifter and the bolt latch bar as the gun reciprocates during firing; and an electronic actuator configured to drive the lever to responsively lift the lifter bar and the bolt latch bar, wherein the mechanism is configured to reciprocate with the gun as it is firing.
 2. The mechanism as specified in claim 1 wherein the mechanism comprises a body having a slot, wherein the mechanism comprises a member configured to slide in the slot when the lifter is lifted.
 3. The mechanism as specified in claim 2 wherein the member is configured to lift in the slot when the lifter is lifted.
 4. The mechanism as specified in claim 3 wherein the member and the gun latch bar are configured to move parallel to each other as the lifter is lifted.
 5. The mechanism as specified in claim 1 wherein the lifter further comprises a bell crank configured to create a mechanical advantage on the lifter.
 6. The mechanism as specified in claim 5 further comprising a clevis coupled to the bell crank, wherein the clevis is directly coupled to the electronic actuator and is configured to retract when the electronic actuator retracts.
 7. The mechanism as specified in claim 5 wherein the electronic actuator is a solenoid.
 8. The mechanism as specified in claim 7 further comprising a solenoid spring configured to return the lever to a resting position when the gun is not firing, wherein the solenoid spring is also configured to allow the solenoid to pull against the solenoid spring to actuate the lever and lift the bolt latch bar.
 9. The mechanism as specified in claim 1 further comprising: a bolt latch pawl pinned to the lifter and spring loaded by a torsion spring in a forward direction, the bolt latch pawl having a bottom flap, and a limit of travel pawl coupled to the bolt latch pawl.
 10. The mechanism as specified in claim 9 wherein the lifter is configured to move upward such that the bolt latch pawl moves upwardly with it, pushing the limit of travel pawl out of the way and lifting the gun's bolt latch bar.
 11. The mechanism as specified in claim 10 wherein when the electronic actuator is released, the bolt latch pawl is intermittently caught on a top surface of the limit of travel pawl.
 12. The mechanism as specified in claim 11 wherein when the bolt travels rearward it is configured to hit the bottom flap of the bolt latch pawl and knock it off the limit of travel pawl.
 13. A mechanism configured to be coupled to a GAU-21 gun having a bolt and a bolt latch bar, comprising: a body; a lifter coupled to the body and configured to be inserted into a rear portion of the GAU-21 gun proximate the bolt latch bar; a lever coupled to the body and the lifter, the lever configured to lift the lifter and the bolt latch bar as the gun reciprocates during firing; an electronic actuator configured to drive the lever to responsively lift the lifter bar and the bolt latch bar, wherein the mechanism is configured to reciprocate with the GAU-21 gun as it is firing.
 14. The mechanism as specified in claim 13 wherein the body has a slot, and further comprises a member configured to slide in the slot when the lifter is lifted.
 15. The mechanism as specified in claim 14 wherein the member is configured to lift in the slot when the lifter is lifted.
 16. The mechanism as specified in claim 15 wherein the member and the gun latch bar are configured to move parallel to each other as the lifter is lifted.
 17. The mechanism as specified in claim 16 wherein the lifter further comprises a bell crank configured to create a mechanical advantage on the lifter.
 18. The mechanism as specified in claim 17 further comprising a clevis coupled to the bell crank, wherein the clevis is directly coupled to the electronic actuator and configured to retract when the electronic actuator retracts.
 19. The mechanism as specified in claim 18 wherein the electronic actuator is a solenoid.
 20. The mechanism as specified in claim 19 further comprising a solenoid spring configured to return the lever to a resting position when the gun is not firing, wherein the solenoid spring is also configured to allow the solenoid to pull against the solenoid spring to actuate the lever and lift the bolt latch bar. 